Connect a Mettler Toledo 8213

I am using the pluggable usb serial adapter to try to connect my mettler toledo 8213 scale. The driver shows up in my device manager (COM 5) but the scale is not sending weight to the computer. I’m using PostalMate shipping software which is compatible with my scale but it doesn’t find the scale either.

Hi Michelle,

I apologize for the delay in answering over the weekend.

Usually, I would look up the manual for the device and find out what settings it needs for serial communications, but for some reason the manual for this scale doesn’t appear to be available online. Also, it looks like a special log-in is needed to access information on the PostalMate site. So I’m limited to just general suggestions.

The first thing to check is that COM 5 is set as the port for the Mettler Toledo 8213 in PostalMate. I could only see an except from an article about this on the PostalMate website, but it looks like you can go to Scale Settings and find the Mettler Toledo 8213 and set it there.

Also, you want to make sure the cable is connected correctly to the scale. Many peripheral devices require a “null modem” cable, which means they won’t work if our cable is plugged directly into. Null modem cables are readily available on Amazon. You can probably find out for sure if this is require by checking the section on serial connection in the manual for the scale.

Finally, it’s less likely, but you may need to change the port settings for the USB-serial cable. If you open Device Manager then right click on the cable and select properties, you can see the tab where you can change port settitngs. If changes are needed, they should be mentioned in the manual. You can also change the COM port here, for example, if your software only accepts COM 1 through COM 4.

I hope this helps.

Plugable Support

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